JPS6220471B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a hot water supply system in which a water heating heat exchanger is provided outside a hot water storage tank, and hot water is stored by circulating it to the water heating exchanger inside the hot water storage tank. This provides a configuration that allows complete removal of air and water from the water circulation system outside the hot water storage tank.

Conventionally, a heat exchanger for water heating was installed outside the hot water tank.
As a hot water supply system that stores hot water by circulating water in a hot water storage tank to a water heating heat exchanger, there is a system shown in Fig. 1 shown in Utility Model Application No. 52-10037. This system includes a hot water storage tank 1, a heat pump unit 2, a compressor 3, a water heating heat exchanger 4, an evaporator 5, a throttle 6, a blower for the evaporator 8, a hot water supply pipe 9, a hot water tap 10, and a water supply pipe 1.
2, a circulation pump 13, a conduit 14 connected to the water supply pipe 12 to the lower part of the hot water storage tank 1, and a conduit 15 connected to the hot water supply pipe 9. In this conventional system, a water conduit 1 connects a water heating heat exchanger 4 of a heat pump unit 2 and a hot water storage tank 1.
The current situation is that a reverse trap occurs on 4 and 15.
Since the water heating heat exchanger 4 is in a completely reverse trap state, in order to completely remove air and water from the water heating heat exchanger 4, the water heating heat exchanger 4 must be removed. Air bleed valve 25 and water bleed valve 26 at the top
It had been set up.

Further, a safety valve is provided from the bottom of the storage tank to the top of the hot water supply pipe 9.

The present invention eliminates the valves for air and water drainage, which are disadvantageous as shown in the above conventional example, and has a safety valve 1.
This provides a configuration that can solve the problem with just .

An embodiment of the present invention is shown in FIG. 2 and will be described below. In FIG. 2, the same components as in FIG. 1 are given the same numbers. In the figure, 1 is a hot water storage tank, and 2 is a heat pump unit, which is located above the hot water storage tank 1 and has an integral structure. The heat pump cycle is composed of a compressor 3, a water heating heat exchanger 4, an evaporator 5, a throttle 6, an accumulator 7, and a blower 8 for the evaporator 5, which are housed in the heat pump unit 2. The water heating heat exchanger 4 has a counter-flow structure, so that the refrigerant discharged from the compressor 3 flows from the upper part to the lower part, and the water flows from the lower part to the upper part, and no reverse trap occurs. 9
is led out from the top of the hot water storage tank 1 by a hot water supply pipe. 10
1 is a hot water tap, 11 is a pressure reducing check valve installed in the hot water pipe 12, 13 is a circulation pump, and the top plate 21 of the hot water storage tank 1 is
and the substrate 22 of the heat pump unit 2, and is substantially fixed on the top plate 21. 14 is a conduit connecting the lower part of the hot water storage tank 1 and the suction port of the circulation pump 13, and 17 is a hot water temperature control valve that controls the outlet hot water temperature of the water heating heat exchanger 4 to be constant. 18 is a safety valve, 23 is a joint, safety valve 1
8, the hot water temperature control valve 17, and the conduit 15 are connected. The other end of the conduit 15 is connected to the hot water supply pipe 9 . Above joint 2
3 at the top, conduit 15, hot water supply pipe 9, hot water storage tank 1
Both the system to the top of the hot water temperature control valve 17, the water heating heat exchanger 4, the circulation pump 13, the conduit 14, and the system to the bottom of the hot water storage structure 1 are designed to prevent reverse traps from occurring. Install piping. The safety valve 18 is connected to the joint 23 at or above the same height. Moreover, 16 is an auxiliary heater 19, a water supply and drainage valve, 20 is a water supply side water stop valve, and 24 is an electrode for electrolytic protection.

In the above configuration, when hot water is stored by the heat pump operation, the circulation pump 13 is operated and the water in the lower part of the hot water storage tank 1 is sent through the conduit 14 to the water heating heat exchanger 4. The water heated by the condensation heat of the heat pump in the water heating heat exchanger 4 becomes hot water, which is kept at a substantially constant temperature by the hot water temperature control valve 17 provided at the outlet of the water heating heat exchanger 4. The water is returned to the top of the hot water storage tank 1 via the joint 23, the conduit 15, and the hot water supply pipe 9. In the hot water storage tank 1, the hot water returned from the top is almost completely separated from the water in the lower part through some intermediate layer due to the difference in specific gravity, and is stored from the upper part of the hot water storage tank 1. Therefore, even if heating by heat pump operation starts when the inside of the hot water tank 1 is completely filled with water, hot water at 55 to 60 degrees Celsius is immediately stored in the upper part of the hot water tank 1. If so, it can be used within a short time after the start of operation. If all the water in the hot water storage tank 1 is heated to 55 to 60°C by heat pump operation, it can be used for normal hot water supply, but if hot water at an even higher temperature is required, the auxiliary heater 16 must be energized. It is also possible to raise the temperature to the required temperature by performing Furthermore, since the circulation pump 13 is operated during the heat pump operation, water circulates through the conduit 14, the water heating heat exchanger 4, and the conduit 15, so there is no fear of freezing within this system. On the other hand, even when the heat pump operation is stopped, the water heating heat exchanger 4 is located above the hot water tank 1, so the water heating heat exchanger 4 easily receives heat from the upper part of the hot water tank 1. In addition, the connection ports of the hot water storage tank 1 with the water heating heat exchanger 4 are open at the top and bottom of the hot water storage tank, and the water piping system is constructed so that no reverse trap occurs, with the joint 23 at the top. Heat exchanger for water heating 4
is located below the joint 23, so even if the water in the water heating heat exchanger 4 is cooled by the outside air, the specific gravity of the cooled water will be greater than that of the hot water in the upper part of the hot water storage tank 1. The hot water naturally falls to the lower part of the hot water storage tank 1 via the circulation pump 13 and the conduit 14, and is then sent to the water heating heat exchanger 4 through the hot water supply pipe 9 and the conduit 15. This prevents the water in the water heating heat exchanger 4 from freezing.

Furthermore, when the outside temperature is such that there is a risk of freezing of the water in the water heating heat exchanger 4, the hot water supply load is large, and the normal hot water temperature setting is set at a moderately high temperature of 85 degrees Celsius. It is clear that since natural convection is more likely to occur, there is practically no need to worry about freezing. In addition, when water is supplied into the equipment for the first time, the safety valve 18 is placed at the top to avoid a reverse trap, so the safety valve 18 is opened and the air inside the equipment is removed from the equipment by water being supplied from the water supply and drainage valve 19. Since the air escapes through the safety valve 18 at the top, no special air bleed valve is required.

Furthermore, when draining water inside the device, by opening the safety valve 18 and opening the drain side of the water supply and drainage valve 19, air enters from the safety valve at the top of the device and water is drained from the water supply and drainage valve 19. The safety valve 18 is placed at the top, and the water heating heat exchanger 4, circulation pump 13, conduits 14, 15, etc., which are the external water piping system of the hot water storage tank 1, have a piping configuration that does not cause reverse traps. The water will flow down naturally and can be completely drained. The safety valve 18 and the water supply/drainage valve 19 are necessary for a normal hot water storage type electric water heater. No special valve required.

In the embodiments, a heat pump device is used as the heating device, but other heating device having a heat exchanger for heating water, such as a gas water heater, etc. may be used.

The present invention described above has the following effects.

(1) By placing the safety valve 18 at the top and piping the external water piping system of the hot water storage tank 1 so as not to cause a reverse trap, air and water can be drained by operating only the safety valve 18 and the water supply/drainage valve 19. Special air vent valves that were required above and below the heating heat exchanger 4 are no longer required.

(2) Furthermore, even if the water in the water heating heat exchanger 4 is cooled, the cold water is sent to the lower part of the hot water storage tank 1, so the hot water in the upper part of the hot water storage tank is not cooled.

(3) Since hot water is always supplied to the water heating heat exchanger 4 from the upper part of the hot water storage tank 1, there is no fear of freezing.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a conventional water heater, and FIG. 2 is a sectional view of a water heater according to an embodiment of the present invention. 1...Hot water tank, 2...Heat pump unit,
3... Compressor, 4... Water heating heat exchanger, 5...
Evaporator, 18...safety valve.

Claims (1)

[Claims] 1. A hot water storage tank and a heating device having a water heating heat exchanger are installed, and the water to be heated by the water heating heat exchanger is taken out from the bottom of the hot water storage tank, and the heated hot water is returned to the top of the hot water storage tank to store hot water. In the hot water supply system, the water heating heat exchanger is configured with the water inlet at the bottom and the hot water outlet at the top, and a safety valve is provided on the hot water outlet side of the water heating heat exchanger, with this safety valve at the top, A water heater characterized by having a water system path from the bottom of the hot water storage tank to the water heating heat exchanger and the safety valve, and a water system path from the top of the hot water storage tank to the safety valve, each of which has a piping configuration that does not cause a reverse trap.